#include <stdio.h>
#define SIZE 100

void concatenate(char s1[],char s2[],char s[]){
    char *p=s1,*q=s;
    while (*p!='\0') *q++=*p++;
    p=s2;
    while (*p!='\0') *q++=*p++;
    *q='\0';
}

int main(){
    // 连接字符串
    char s1[SIZE],s2[SIZE],s[SIZE];
    printf("input string1:");
    scanf("%s",s1);
    printf("input string2:");
    scanf("%s",s2);
    concatenate(s1,s2,s);
    printf("new string:%s\n",s);
    return 0;
}